I forgot - what were you'all using - 18 awg for power on these guys?
The watts for the Gridseed 5 is:
8 watts (0.67 amps @ 12 volts) for LTC only
52 watts (4.33 amps) for BTC only
60 watts (5.00 amps) for combined BTC/LTC
Based upon this chart
http://www.powerstream.com/Wire_Size.htmThe recommended gauge wire is:
23 gauge for 0.729 amps (0.67 required for LTC only)
15 gauge for 4.7 amps (4.33 required for BTC only)
14 gauge for 5.9 amps (5.00 required for combined BTC/LTC).
Given that the gauges are conservative, you can probably get by with 24 gauge (.577 amps) for LTC only mode, and 15 gauge for combined mining.
Note: If you use 23 gauge wire, and inadvertently invoke BTC mode, you risk melting the wire. 18 gauge would survive a short period of time, and may even work for a while. But, I wouldn't plan on BTC mode with 18 gauge.